1. Field of the Invention
The present invention relates to a bunch-winding releasing device for a package of the type which is formed by inserting the beginning end of a yarn into a slit formed in the end of a bobbin, bunch-winding the yarn and winding the yarn through a nip. The present invention further relates to a bunch-winding releasing device for drawing a yarn in a slit in which the yarn is removed from the slit when the bunch winding is released and yarn from a nip point and yarn from the slit are simultaneously drawn.
2. Description of Related Art
In a winding machine for tire cords such as polyester or nylon, a package which winds a continuously spun yarn to form a full winding is sent to the desired succeeding step or shipped as the product.
As shown in FIGS. 19 and 20, in such a package the beginning end of yarn is first bunch wound at 1 on the end of a bobbin B. The yarn is then ordinarily wound on the bobbin B to form a package P. The yarn is then bar-wound at 2 to a predetermined length about the outer periphery of the package, and is then shipped as the product. The yarn end of the bar-wound portion 2 is shown at reference character 3.
The bunch winding 1 is applied to the bobbin B by forming a slit in a peripheral direction of the bobbin B, engaging the beginning end of the yarn in the slit, winding the yarn about the end of the bobbin B, applying the bunch winding 1 thereto, and thereafter effecting ordinary winding. It is sometimes desirable to remove the beginning end of the bunch wound yarn, in order to join the beginning end of yarn with yarn on another package. However, the beginning end of yarn cannot be easily removed since the beginning end of the yarn is positioned at the lowermost or innermost layer of the bunch wound yarn.
In view of the foregoing, the present applicant has proposed a device for releasing a bunch wound yarn to draw the beginning end of yarn thereof (see Japanese Patent Application No. 91020/1987, opened for public inspection under the Provisional Patent Publication No. 63-258378 on Oct. 25, 1988, entitled "Device for Drawing a Bunch Wound Yarn").
The device disclosed in the aforesaid Japanese Patent Application is described with reference to FIGS. 14 through 17. Additionally, an example of apparatus which can perform several functions described below (in the background of the invention section), e.g., movement between stations ST1, ST2 and ST3, operating a roller 4 and operating a roller 5, is shown in U.S. Pat. No. 4,760,969 to Otoshima, et al. and assigned to the assignee of the present invention (with reference to conveyor 1, roller 58 and roller 101, respectively of the Otoshima, et al. patent).
In a first stage (designated ST1), a bunch wind 1 is prepared for release by a feed roller 4, as shown in FIGS. 14 and 15. The bunch wind 1 is moved to a second stage (designated ST2), in which the bunch wind prepared for release is released by a loosing roller 5, as shown in FIGS. 16 and 17.
The operation of the feed roller 4 for preparing the release of the bunch winding is described with reference to FIGS. 14 and 15.
A yarn bunch is wound at 1 on a bobbin B1 of the package P1. The yarn has its nip point N located at the outermost layer, as shown in FIG. 14. The beginning end of the yarn in the innermost layer is positioned in a slit S (FIG. 16) formed in the bobbin B1.
A feed roller 4 is operated so that the yarn YN in the bunch winding 1 is moved toward the package P1 in order from the yarn closest to the nip point N. The fore end 4a of the feed roller 4 comes into contact with the peripheral surface of the bobbin B1 between the bunch wind 1 and the nip point N. In that state, when the roller 4 rotates in a direction opposite to the winding direction of the bunch wind 1 (as indicated by the arrow 7 in FIG. 14), the fore end 4a impinges upon the yarn YN extending from the nip point N to the bunch wind 1 and feeds the yarn YN toward the package P1, as shown in FIG. 15.
As a result of the process described above, the yarn of the bunch wind 1 is moved by the feed roller 4 from its outermost yarn toward the nip point N (package side), whereby the beginning end of the yarn positioned in the slit S is exposed to the surface of the bobbin B1.
After the preparation for releasing the bunch wind has been completed, the package P is moved to the second stage ST2, and the bunch wound yarn is removed by the loosing roller 5. This is described with reference to FIGS. 16 and 17.
First, the fore end 5a of the loosing roller 5 comes into contact with the bobbin B2 in the vicinity of the slit S. In that state, the loosing roller 5 is rotated in the winding direction of the bunch wind (as indicated by arrow 8 in FIG. 16).
When the loosing roller 5 rotates as described above, the roller 5 loosens the yarn from the beginning end of the yarn. The bunch wound yarn is sucked into a suction opening 9a within a support body which is inserted into the bobbin B2. The bunch wound yarn is sucked and removed from the bobbin B2.
After the bunch winding has been released as described above, the support body 9 is moved away from the end of the bobbin B2. The yarn sucked into the support body 9 is suitably held so as not to be drawn out, as shown in FIG. 17. The beginning end of the yarn positioned in the slit S may be removed as shown in FIG. 18.
However, if the yarn is firmly positioned in the slit S, then the beginning end of the yarn cannot be removed from the slit S even if the support body 9 is moved. The yarn YN on the side of the nip point as well as the yarn YS on the side of the slit S are drawn between the bobbin B2 and the suction opening 9a of the support body 9, as shown in FIG. 4. Even if a predetermined length of the yarn YN on the side of the nip point is wound on the bobbin B, the yarn YS on the side of the slit S is a hindrance. The support body disclosed in Japanese Patent Application No. 91020/1987 (referenced above) needs to be reciprocated many times until the yarn YS on the side of the slit is removed.
It is an object of the present invention to provide a device for drawing a yarn in a slit in which the yarn on the side of the slit can be easily removed when the yarn is drawn.